Magnet



N0.'.'750,594. PATENTED JAN. 26, 1904. H. F. CAMPBELL.

MAGNET.

APPLICATION FILED MAY 16, 1901.

N0 MODEL.

No. 750,594. Patented January 26, 1904.

UNITED STATES PATENT OFFICE.

HENRY F. CAMPBELL, OF BOSTON, MASSACHUSETTS, ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, TO NATIONAL MAGNETIC MINERAL SEPA- RATING COMPANY, A CORPORATION OF MAINE.

MAGNET.

SPECIFICATION forming part of Letters Patent No. 750,594, dated January 26, 1904.

Application filed May 16, 1901. Serial No. 60,432- (No model.)

T whom it y wern: 1 of the lower half of the magnet is secured a Be it known that I, HENRY F. CAMPBELL, of pole-piece 7 by means of bolts 8 passing Boston, in the county of Suffolk and State of through slots 9 in the pole-piece into the ends Massachusetts, have invented certain new and of the bars 1. By this construction the pole- 5 useful Improvements in Magnets, of which the piece 7 may be adjusted. The upper edge of following is a specification. the pole-piece 7 is serrated to form projec- This invention relates toanew and improved tions 9 and intervening spaces 10. A spool 55 magnet; and it consists in the novel features of 11 is arranged upon each arm of the magnet construction and relative arrangement of parts in order to vitalize the magnet in the usual hereinafter fully described in the specificaway.

tion, clearly illustrated in the drawings, and A magnet of the kind described is capable particularly pointed out in the claims. of exerting a magnetic pull of great force 60 Reference is to be had to the accompanying with particular reference to the form shown in drawings, forming a part of this application, Figs. 1 and 2. Such magnets are easy of con- 15 wherein like characters are used to indicate struction and inexpensive. By reason of the like parts wherever they occur. gashed or staggered surface of the poles in Figure 1 is a perspective view of a magnet the form shown in Figs. 1 and 2 zones of vary- 5 constructed in accordance with my invention. ing intensity are produced, the power and rel- Fig. 2 is a longitudinal sectional view of a ative potentiality of which may be varied as modified form. desired by varying the strength of the cur- Referring to Figs. 1 and 2, 1 represents a rent passing through the spools and by varyseries of curved bars of magnetic material, ing the size of the bars, their relative distance 7 each having the general shape of one-half of from one another, or the size and shape of a horseshoe. A series of these bars, here the notches and projections at the end of the shown as six, although the number may be pole-pieces. By the hingeconstruction shown varied, arefastened together by pins2in order in Fig. 1 the pole-pieces of the magnet, as to secure said bars in proper relation to each stated, may be adjusted toward and from each 75 other and to maintain them in position. The other and toward and from any material or said series of bars are pivoted at their curved object placed between the poles. hen adends by means of a pintle-plate 3 and pins 4, justed, the two parts of the magnet may be projecting from the ends of the bars 1 into held in their adjusted position by any suitable the plate, as shown. Any other form of conclamping or adjusting device or apparatus. 80 struction may be employed, if desired, the The form of magnet shown in Figs. 1 and2 purpose being to hinge the horseshoe-magfor some classes of work I prefer to construct net at its rear part in order to permit the adin hinged form, as shown in Fig. 1, while for justment of its poles, hereinafter described, to other classes of work the laminae will not be and from each other. The hinge connection divided, but will be continuous from pole to 5 may be of such a character that the poles Will pole, as in Fig. 2. remain in any position of hinged adjustment The particular form of magnet herein de- 4 by reason of the construction of the hinge, or scribed and claimed is designed for use in conthe adjusted position may be maintained by nection with that type of magnetic ore-sepaany desired mechanism. The bars 1 are seprator in which the ore or the material is sub- 9 arated from one another except for a short jected to the action of a magnet while supportdistance at the ends, forming insulating 0001- ed on a belt or its equivalent moving past the ing air-spaces 5. The ends of the bars 1 formpole or poles of the magnet. As hereinbefore ing the upper arm of the magnet are serrated stated, the gashed or staggered surface of the to form projecting notches 6 and intervening poles (shown in Figs. 1 and 2) results in the recesses or spaces 5. To the ends of the bars production of zones of varying intensity.

These zones therefore cause the ore or other material passing the magnet to be agitated violently to aid in the separation of the particles from each other, as will be readily understood. The horseshoe form of magnet (shown in Figs. 1 and 2) provides a space between the opposite poles of the magnet, which is open to permit the material under treatment to be passed between said poles and to be therefore subjected to a stronger field of force than when subjected solely to the fields of force at the end of a simple bar or series of bar-magnets.

As hereinbefore stated, the pole-piece 7 is adjustable by means of the screw 8 and slots 9. This enables the intensity of the magnetic field to be modified without changing the position of the bars of the magnet.

I do not wish to be understood as limiting myself to the precise form of the projections 6 and the spaces 5, since other forms of projections and intervening spaces might be employed, the purpose being to interrupt the surface of the pole, so as to provide or form a plurality of zones of varying intensity.

Instead of separating the laminae or otherwise insulating the laminae from one another I prefer in cases where great potentiality is desired to have said laminae in contact and not insulated from one another.

Having thus explained the nature of my invention and described a way of constructing and using the same, although without having attempted to set forth all the forms in which it may be embodied or all the modes of its use, I declare that what I claim is* 1. A magnet comprising parallel horseshoeshaped bars arranged to have an air-space between them, means for magnetizing said bars, and a pole-piece adjustably mounted upon the lower ends of the said bars.

2. A magnet comprising parallel horseshoeshaped bars each of which is provided with a cut-out portion whereby air-spaces are formed between the bars, means for magnetizing the bars, and an adjustable pole-piece mounted. upon the ends of the lower portion of said bars.

3. A magnet comprising parallel horseshoeshaped bars having a portion of their contacting faces cut away to form an air-space, the upper ends of said bars being serrated, means for magnetizing the bars, and a pole-piece adjustably mounted upon the lower ends of the said bars, the portion of said pole-piece adjacent to the upper ends of the bars being serrated.

4. A horseshoe-shaped magnet having means whereby the distance between its ends or poles maybe varied, and having one of its ends or poles gashed or formed with a staggered or interrupted surface to produce magnetic zones of varying predetermined arrangement and potentiality, all of the projecting portions of each pole having the same polarity.

In testimony whereof I have aflixed my signature in presence of two witnesses.

HENRY F. GAR [PEELL Witnesses:

G. F. BROWN, E. BATCHELDICR. 

